So the "alien" is from California! The most frequent Sci Fi elemental substitution is Si instead of C, so who would have guessed that As instead of P?!

At their conference today, NASA scientist Felisa Wolfe Simon will announce that they have found a bacteria whose DNA is completely alien to what we know today. Instead of using phosphorus, the bacteria uses arsenic. All life on Earth is made of six components: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. Every being, from the smallest amoeba to the largest whale, share the same life stream. Our DNA blocks are all the same. But not this one.